This invention relates glass-tube fuses, and more particularly to the fuse element in a glass-tube fuse, which is fused upon application of over-current.
Essential ones of the characteristics required for a fuse are a fusing characteristic required when overloaded, an interrupting characteristic required when over-current such as a short-circuit flows, and a surge characteristic against a surge which may caused by opening or closing a line for instance.
There have been proposed a variety of fuses, which intend to improve a particular one of these characteristics. Referring only to the fuse elements, heretofore a fuse element made by twisting a plurality of strands instead of a single strand or a fuse element made by winding a metal wire around one or more cores are proposed.
However, glass-tube fuses which have the abovedescribed characteristics, and are stable in characteristic, and which can be readily manufactured have not yet been provided.